The Hi-Fi Five Episode 29: Field Coil Loudspeakers

The HiFi Five Episode 29:  Field Coil Loudspeakers

GUESTS

Frank Doris --  Editor of Copper Magazine, Senior Associate Editor at Positive Feedback

Rich Pinto -- Founder and Designer, Treehaus Audio

Peter Qvortrup -- Founder and Managing Director, Audio Note UK

Ken Songer -- Founder and Designer, Songer Audio

TOPICS

Why are field coil drivers something special sonically?

Permanent magnets and electromagnets both generate a magnetic field.  Why does the sound coming off the cone sound different when it's moved by one type of magnet versus the other? What is the technical advantage of using an electromagnet?Are most field coil drivers fabricated in-house or bought off the shelf?

Does the type of power supply — tube or solid-state — affect the sound of the driver?

How does the sound change as you change the power supply voltage to the electromagnet?  Why?

Is there any scenario where a permanent magnet driver is the better engineering choice than a field coil driver for a loudspeaker?

Are there any specific objective measurements which demonstrate the technical superiority of field coil drivers?

Can you imagine traditional loudspeakers manufacturers like Magico or Wilson moving to field coil drivers?

Transcript

SPEAKER_02 0:01

Welcome to the 29th episode of the High Five Five. I'm Ron Resnick. Please like this video and subscribe to the channel. Tonight's guests, Frank Dorris, is the editor of Copper Magazine and a senior associate editor of Positive Feedback. Frank was the technical editor of The Absolute Sound during the 1980s and 1990s, which makes him truly OG from the Harry Pearson era. Rich Pinto is the founder and designer of Treehouse Audio, which makes field coil loudspeakers and tube electronics. Treehouse was established in 2017. Peter Kortrop is the founder and owner of Audio Note UK. Established in 1991, Audio Note UK offers a full suite of components, and the top-of-the-line loudspeaker uses field coil drivers. Ken Sanger founded Sanger Audio in 2018 after a career at Microsoft. Sanger Audio makes ported and open baffle field coiled speakers. First, a little background on field coils. A speaker has a magnet, a coil, a suspension, and a diaphragm. When an electrical signal music is applied to the voice coil, the interaction of the voice coil and the magnetic field moves the cone. So the only question is, is that magnetic field generated by a permanent magnet or by an electrically powered magnet? Remember in high school, you have a little U-shaped thing that picks up metal, that's a permanent magnet. When in science class we wrapped wire around a nail and attached to a battery, that's an electromagnet. In each design, the voice coil goes through the magnetic field. It's just a question of whether the magnetic field is generated by a permanent magnet or an electromagnet. When loudspeakers were first invented, permanent magnets were very large and expensive. And so most of those loudspeakers were engineered with field coil drivers. As the size and price of permanent magnets declined, field coil drivers kind of became obsolete until they were resurrected by designers today, including some of the designers who are our guests on this episode. Welcome everybody.

SPEAKER_03 1:50

Thank you for having me, Ron.

SPEAKER_02 1:52

Question number one: Why do you feel that field coil drivers are something special sonically? Peter.

SPEAKER_00 2:01

Well, it's uh it's actually pretty obvious if you listen to them. Um I think we we we make speakers that are acoustically identical. One the cheaper ones have a ferrite magnet, the more expensive ones have an eco magnet, and the most expensive have field coils. And when you go from one to the other, it is patently obvious uh that the field coil is far, far, far superior to any of the uh any of the other magnetic materials, or the hard magnetic materials as we call it.

SPEAKER_02 2:37

Okay, but superior how? It's easy to say superior. What are you here that's different?

SPEAKER_00 2:42

Well, they they they are they're more organic, they there is less noise in the background. Uh we can discuss the noise later if you like, but uh there are they have a kind of life and and they draw the the instruments in in a way that uh no other uh no other uh magnet material does.

SPEAKER_03 3:09

What do you hear that's different? Um, you know, I don't know, it's it's a tough question for me, Ron, because I so can can a field coil sound special? I would say uh yes, it absolutely can. And I think we make a field coil uh that does sound very special comparative to most of what you hear at a show. But for me, you know, it's there's so much that goes into what makes any driver sound the way that it does. You know, I think part of that, you know, are some things that I think, you know, in in some of the questions that you're going to be asking later in the show, you know, we might dive into about you know some differences in uh you know in the magnetic field and its interaction with a voice coil in a permanent magnet versus a field coil. Um, but I think it's also important to note that um that a field coil isn't a shortcut around good engineering. Um a poorly designed driver is going to sound like a poorly designed driver, and that's going to be the case, whether it's a permanent magnet or a field coil. So, you know, when I when I think about why our driver sounds special or some of the other field coils that I've heard it shows, you know, really grip me. Um part of that story is that they've started with the foundation of uh a field coil and the you know and the advantages of a field coil, but uh, you know, but it has every bit as much, I think, to do with the decisions that they made in the suspension and the comb. And you know, and in other words, you know, all of the little pieces of the implementation of that field coil that are a big part of the story, too. So um, so you know, is a field coil special? I I would say yes, but there are also uh you know some really fantastic and special sounding permanent um permanent magnet drivers, also. So it's it's a nuance. I wish there was a very simple answer to many of these questions, but you know, you often find yourself, as you do with everything in audio, you know, finding out that um, you know, the the field coil is part of the system of you know uh of a driver, and then that driver is then a part of the system of a loudspeaker, and then generally speaking, uh, you know, its interaction with the amplifier plays a role, and and all of those things contribute to uh you know to what you end up hearing in the listening chair in your listening space.

SPEAKER_05 5:43

Rich. Yeah, I mean I agree a lot with what Ken just said. Um, you know, a field coil is not um it's not a magic bullet to make a great speaker. Um sonically in field coils, I hear um more micro detail, I think is what I notice. Um they don't need to be as high of a volume level to kind of get you into the music, which is why I really like about their peculiar aspect of their sound. Um, and then you know, I love tube amplifiers, and fuel coils are more efficient, more efficient speaker, you need less power. It's easier to design, create tube amplified amplification around that. So, as a system, I find field coil is just a good way to produce the music when you're kind of looking at a complete system approach because you know, higher high efficiency to me makes everything easier. It's like a lightweight sports car. You're not fighting the physics as much.

SPEAKER_02 6:37

But there's nothing sensitivity in the use of field coil technology or independent variables.

SPEAKER_05 6:42

Um, well, field coil, you have a stronger um magnet, so your efficiency generally goes up.

unknown 6:48

Okay.

SPEAKER_05 6:48

So you're kind of a better starting point.

SPEAKER_02 6:51

The only time I'm gonna probably answer tonight and the episode is all I know is every time I hear a field coil speaker, I like it. Whether it's your guys, whether it's uh a sangar, an audio note, a treehouse, uh the new Andrew Jones Troubadour, the Wolf von Lange stuff, all I know is I hear a greater naturalness in the mid-range. And I have liked literally every single field coil I've heard. So I don't know. I definitely think there's something to the technology. Question number two permanent magnets and electromagnets both generate a magnetic field, as we've said, but why? You guys answered kind of technically. Why does the sound coming off the cone sound different if it's in the magnetic field of a field coil driver versus a permanent magnet? What is the difference in what the cone is experiencing that causes us to hear the differences we think we're hearing between field coil drivers and conventional drivers? What's the technical advantage of using an electromagnet?

SPEAKER_00 7:51

Well, the technical advantage as far as we're hold on, let me get Ken here.

SPEAKER_02 7:55

Hold on.

SPEAKER_00 7:55

Okay, sorry.

SPEAKER_02 7:56

Ken.

SPEAKER_03 7:57

Um, well, I guess uh you know this touches on something we were discussing just a moment ago, or Rich mentioned, which is I think part of that is, you know, and again, I'll keep returning to the show environment and you know, an uh an experience where you get to go from you know a whole series of permanent magnet experiences and the few field coils that are out there, you know, and then as you were you were mentioning, that you notice, you know, uh substantial sonic improvement in the field coil experiences. Um, you one difference between those two experiences, and this is generally speaking, is that the the force of the magnet, the strength of that motor uh for a field coil is more often than not going to be substantially higher than it is in the permanent magnet drivers that you're hearing in some of those other systems. So I think that's one part of it. Um, another part, and you know, I mean again, I don't know, maybe I should mention this briefly. I mean, I'm I kind of come at this from the perspective of an artist. Like I didn't set out with the idea that I was going to make a fantastic field coil loudspeaker, and then you know, it uh listed out all of the reasons why I could predict success for that driver. I I came at it as an artist, and I just happened to make uh a driver that when I played it for the first time was the most sensational sounding thing I'd ever heard in my life. And and I and since then I've been trying to refine my understanding of why that's the case. So um, so there's the magnet magnetic strength. Uh as I understand it, there is also the um the flux gap, the the uniformity of the flux in the gap of a field coil versus uh a permanent magnet. So, you know, so what you have in in a dynamic driver is you have you know a uh uh a magnetic circuit, you know, which is either that field coil or the permanent magnet, um, and then you have a voice coil inside of it and it's generating its own magnetic field. So, you know, what what happens in a in a permanent magnet is that that modulation interacts with the uh the field of the motor, of that permanent magnet's motor, um, and it causes a distortion uh because the the the field of the permanent magnet is affected by that modulation that's going on with uh with the voice coil as it receives the signal. Um in a field coil it's different. Um it is the magnetic field is being generated by a constant DC voltage, and and because of that, um it it interacts with that modulation from the voice coil differently and resists it strongly. So you don't get any of that distortion that you're getting from a permanent magnet as those two magnetic fields interact. It's virtually zero in a field coil. So that's um that's that's another reason. Uh, and then the third reason I would say is that as I understand it, the way that a field coil handles back EMF from the voice coil, again, as it's receiving that signal um and oscillating in the gap is is different in a permanent magnet, which depends upon the damping factor of the amplifier. Whereas it's filtered in some respect in a field coil driver because both the field coil itself and the amplifier um are working against that back EMF and uh and and essentially canceling it out to zero. So that's my understanding of you know just some of the more technical reasons why you know you're you're hearing what could be considered a more uh lifelike, accurate, distortion-free, um, and and overall generally, more compelling experience of the music when you're hearing a well-designed vehicle versus a permanent magnet driver.

SPEAKER_02 12:16

Peter.

SPEAKER_00 12:18

Well, the basically what happened, you can see it in the hysteresis loop of the different magnetic materials. If you compare the hysteresis loop of a of a uh ferrite magnet with an al-Nico magnet and uh and then a field coil that all have the same gap flux, then what you'll see is that the uh that the um hard magnetic materials and and uh particularly ferrites have a very wide loop where the loop in the uh in the um in the field coil is very, very narrow. And uh what that what what does that mean? Well, what it means is that when the when the coil, when the speech coil moves in the field, what happens in a permanent magnet is that the field bends. It doesn't bend linear in terms in in a linear way like I'm showing with my hand now. What it does is it it jumps, so it's overcome by the movement. Now you told uh Ken talked about um about back EMF. And one reason you get a lot more back EMF from uh from um speakers with permanent magnets, uh, is precisely for that reason. Because that is what disturbs then it depends on how how you deal with it, but it depends uh disturbs the uh the um um the way the amplifier sees the speaker. Now in amplifiers with output transformers, like valve amplifiers, you you by and large short the the back EMF to the power supply, to the ground of the power supply, and get rid of it. So amplifiers with output transformers are less sensitive to this. In a transistor amplifier, what what it does is it enters the feedback loop. As the feedback loop gets to the output of the amplifier, it meets the back EMF. Some of that is then shipped back to the input, causing additional distortion and and all kinds of strange um uh time displacement effects and other sort other things like that. Now, if you then look at a field coil, the field coil has a much, much stiffer field. And the reason for that is that it will resist the movement, it'll resist moving by simply drawing more power from the power supply. So it does not have the problem that you have in a permanent magnet, that the permanent magnetic field is a resource that if you start trying to use part of that resource to make sound, it will simply move away from the uh from the coil as the coil moves. And of course, in music, the coil never stops moving, which means the field is in constant flux, and and therefore that creates a lot of distortion. Now I've often described as so few speakers on the market that uh that do not have these permanent magnets. We have attuned our hearing to that so much to the extent where we can we can barely hear it. It's only really when you remove it by having a per a field coil magnet that that uh you suddenly realize that that noise is actually there all the time.

SPEAKER_05 16:07

So well, first I appreciate Peter and Ken answering all the hard questions. Um we'll send the invoice. Um, but I will also add that um I feel one of the other technical advantages is that the um the fuel coils um parameters are adjustable via the voltage. So um, you know, depending on the speaker design, if it makes sense, if you adjust the fuel coil voltage, you adjust the sodomic signature of the speakers. Um, you're affecting efficiency as you change the voltage, but you're also changing the the cue. So you can adjust the speaker a bit for, you know, in our case, we have an open baffle, so there's a lot of adjustability because you're have a lot more room effect. But in any circumstance, and with the fuel coil, adjusting the voltage allows you to kind of tune the sound a little bit to personal preference into your upstream electronics, which is a nice advantage over um permanent magnet.

SPEAKER_02 17:02

Frank, do you ever remember setting up a field coil outspeaker for Harry back in the day?

SPEAKER_01 17:07

No, no, and um I I just wanted to say that my attraction to the field coil speakers, no pun intended, is uh it's kind of an indescribable naturalness or an ease or a sort of a relaxed presentation. I like to use the analogy of the first time I heard an optical cartridge, it presented reality where you really felt like, wow, this is a really great presentation of reality, but it's different from you know a moving coil or a moving magnet, and trying to wrap my head around quantifying why it's different and explaining it. And you guys have covered a lot of a lot of ground uh in that regard. But um, no, I I I never got to set one up. I'm I'm I'd be intrigued by uh by trying that at some point, especially when you could if you can vary the voltage and tailor the sound. Oh my god, it'd be like I could see like people who would just VTA for each record. I'd I'd be going crazy and trying to tweak it and go into complete audiophile realm.

SPEAKER_05 18:15

You know, I have to I have to add in some people kind of get fixated on that, but I find that most of my customers um once they find a voltage they like, um, they kind of just stick with it. And you know, I there are other aspects of uh audio setup where I will constantly fiddle with things, but the field coil voltage, I kind of you know, give it a couple listens and it kind of just stays where it is.

SPEAKER_00 18:36

So that's what there is an optimal voltage which uh at which a uh a given driver will will uh have the best output. Well, it'll be a voltage and current combination, it's not just the voltage.

SPEAKER_04 18:52

Yes.

SPEAKER_00 18:52

Oh, by the way, we we actually make a moving coil cartridge with a field coil. Do you have one as well? How do you power it? Well, we power it with two extra wires that run through the tonearm, and uh it has a little power supply, which uh gives out 1.2 amps at I can't remember what the voltage is now.

SPEAKER_02 19:18

I thought only the Dava was the only field coil cartridge around. So you so Audio Node has one, and and Rich, you have a field coil cartridge as well?

SPEAKER_05 19:24

Oh, I have the Dava on my personal phone.

SPEAKER_02 19:26

Okay, so yeah, yeah.

SPEAKER_00 19:28

Um well, I mean the the original design of the field coil cartrid came from uh came from uh uh Mr. Kondo in Japan. We bought the design off him in 1989. Interesting.

SPEAKER_02 19:43

Question number three Are most field coil drivers fabricated in-house or bought off the shelf? Ken, I know you do yours completely in-house. Um uh Rich, uh, how do you source your field coil driver?

SPEAKER_05 19:56

Yeah, so my field coil drivers are built by um Oleg Rulett, he's in Germany. Um, he has a huge stash of vintage telefunken um clank filmera drivers that he kind of um resto mods and rebuilds. So that's my source for my field coil drivers. Um, you know, they're a full-range driver, very conceptually similar to Ken's, but kind of uh the uh hundred-year-old version in some ways. Um yeah, good. Sorry, sorry. No, that's that's uh so you know, those are fabricated. Um, you know, there's not a lot of off-the-shelf field coil solutions um out there because they're yeah, it's a more of a unique uh niche kind of product.

SPEAKER_02 20:32

And Peter, you make yours in half, I think.

SPEAKER_00 20:34

We make everything in house. All of it. We source we source all the parts um ourselves, together with everything else. Pain in the ass, that is.

SPEAKER_02 20:51

Question number four, and this gets back to Peter what you were just saying. Does the type of power supply, tube or solid state, affect the sound of the driver? Peter, how did you decide whether to use a tube power supply or a solid state power supply? And what's the difference in sound?

SPEAKER_00 21:06

Well, we haven't finished experimenting with a tube power supply. I'm not a hundred percent sure that a tube power supply is stable enough to maintain a constant flux over time. Um there are there are tubes that might be suitable for this, uh, like the 6AS7 and the 6080 and a few others. Uh, the problem is whether they are really that suitable for that is is uh remains to be seen. But it is an area where we're currently looking at. So uh put me on in number 31 or 32, and I'll tell you.

SPEAKER_05 21:48

Rich, I think you use a two power supply. Yes, we do use a two power supply. It's a pair of uh six CJ3s um running as diodes, and then we use a uh adjustable voltage source. Um on the treehouse field. Coils because they're vintage origin. Um, we run about 100 volts on the coil, so it's a lot less current. So that kind of enables a lot of um enables tube rectifiers. Where in the um more modern 12 volt field coils, um, it's so much current, there's not a lot of tube rectified options. Um, I know um classic audio uses um some tongue guard tubes to achieve that. Um, and I find the power supply is important, but it's not as critical of a design as like the amplifier. I think any kind of good linear supply gets the job done pretty well. Um, and the you know the variation in sound quality between a good supply and a fantastic one isn't huge.

SPEAKER_02 22:43

Ken, how did you? I know you use solid state, how did you choose between solid state and tube when you were developing your system?

SPEAKER_03 22:49

Um, you know, the choice was almost kind of made for me because I mean for me, it was going to be a Herculean task to design the driver that I wanted to design in the loudspeaker itself. And then, you know, and and I think I think that I benefited from the fact that in those arenas, you can somewhat rely on excellence of execution to get the kind of result that you want. You know, in other words, you know, for for some things, uh, you know, you either know how to do brain surgery or you don't, you know, and and there is no substitute in terms of uh excellence of craftsmanship that um that can replace them. And so for me, when it came down to uh you know what kind of power supply was I going to use for the field coils, I had no choice but to rely on that brain surgery knowledge of you know partners in the industry to make good decisions from there. Um, I mean, I've I've heard the field coil are field coils with a uh you know a variety of different power supplies of different, you know, varying levels of quality. And I think that the same things that apply anywhere else apply there, which is that if the power supply is, you know, is is noisy or unstable or poorly regulated, um, you know, it matters a great deal in the sense that that is then, you know, I mean it's very in a very real sense, it's it's a part of the system. That power supply is because it's providing that magnetic field that you're relying on. And um, and so in that regard, you know, quality I think does make a big difference. Um, you know, having a well-regulated power supply is uh, you know, is important. Uh, but as far as the difference between tube and solid state, you know, for me, there um, you know, I I haven't heard our our loudspeakers with a tube power supply. So, you know, I can't really say from direct experience, but if I had to guess, I'm kind of more in you know in riches camp in the sense that um, you know, I think that execution and circuit design are are likely to be more dominant than solid state versus two in that part of the system.

SPEAKER_02 25:09

Question number five. How does the sound change?

SPEAKER_00 25:14

On the on the power supplies aspect, one of the things we found was that the uh that the um that made a great deal of difference was the component choice in the power supply, like the type of electrolytic capacitors or capacitors as a general rule, or the uh the uh the uh chokes, or you know, the design of the of the uh the uh wire and so on. That made to my considerable surprise a lot more difference than I would have thought. And we do a lot of experiments with stuff like that. And you know, what was the difference?

SPEAKER_02 25:54

What difference were you actually hearing?

SPEAKER_00 25:56

Well, I uh I mean it it's along the same lines as as the type of iron you use in the uh in the um in the transmitting cup that you have the coil internally and then you you have a cup around it with which consists of it really is what the speaker looks like. The the quality and the efficiency of the iron has a very strong bearing on the uh on the quality of the sound of the field coil. The more efficient the iron is, the uh the better the the uh the the field coil sounds. For the all all other aspects being equal, the uh the uh the uh quality of the iron has a dramatic effect on the uh on the quality of the sound. Um and I I think that that's an area that's largely overlooked uh by a lot of the people that make um um uh make field coils. I remember speaking to the uh the people that make the phi uh field coil speakers in France, and they were unaware, they were complaining that their units ran quite hot. Because most of these speakers are used, or drivers are used in in open battles, so it doesn't matter uh whether they get get that hot or not, as long as they don't set fire to the cabinet. Um but the uh the for us it makes a big difference because we have two two drivers in a sealed cabinet, so the amount of heat that's generated is a major problem. On the early prototypes, I melted the tweeter cone. Wow, that's impressive. Oh no, no, I forgot to switch them off overnight and I came down in the morning and put the sound, put the music on, and I thought there's something not right here. This sounds very peculiar. I looked at the cone and it all swiveled and disappeared.

SPEAKER_03 27:53

I've never set anything on fire, but it definitely like I think the longest I've ever run one of our S1X speakers is four straight days. And it was like a poly hobby oven in there.

SPEAKER_00 28:04

I mean, it was nothing dangerous, you know, but uh but no, I mean it's not dangerous, Ken, but it does have an effect on on the uh on the uh how long the coil on the driver lasts, for example. Right. I always recommend that people just shut down the system overnight. So do we, yeah, even though ours can now run because we we went we dropped on the base unit from 45 watts uh using a standard magnetic ion to 15 watts. Oh, that's great. That's quite a good idea. Given the price of electricity in the US with all these data sensors, you may find that of interest.

SPEAKER_02 28:45

Question number five: how does the sound change as you change the power supply voltage? So imagine you have a little knob on these things, and the owner can change the voltage a little bit on the power supply. Rich, what do you hear changing as you change the voltage?

SPEAKER_05 29:03

Yeah, so on, you know, we have about a 20% um adjustability range in our speakers. Um, if you have it on the lower end of the adjustment, um, the sound's a bit more relaxed. Um, your cue is higher. Um, so it's a little more of a relaxed sound, a little bit lower efficiency. Then as you raise the voltage, you kind of literally tighten up the sound a bit. Um, things are a little more precise, a little bit more um traditional of a hi-fi um presentation. Um you kind of have to tune your ear out a little bit because you're changing efficiency and the sound at the same and the quality of the sound at the same time. And you know, the ear naturally wants to think the louder thing is better. So it takes a little bit of discipline to kind of wire that out of your brain, just kind of listen to the sound presentation. But um, yeah, it's I'm it's kind of you know, as you think, the stronger the magnetic field, the tighter things become.

SPEAKER_02 29:59

We're getting a little bit of a feedback thing. Does everybody uh have their phone off and no other device on? So we're not listening to through some other mechanism. Yeah, so quiet here. Okay. Uh Peter, how do you hear the sound changing from the speaker as you change the voltage?

SPEAKER_00 30:17

Well, then and and our speaker is more complicated than that because our speakers are set up so that they have a frequency response that they match to a frequency response that's within about half a dB across the band. And we have a setup system that does that. Now, if you change the voltage or the current on the uh on the drivers, you change the flux. And when you change the flux, you change the frequency response. And as a result of that, you we can clearly hear that the alignment between the woofer and the tweeter uh they go out of alignment uh once we make a change that over a certain level. And it's actually very, very tight that level. So we use a constant voltage stroke current power supply, which uses a we have a patented uh uh power supply configuration that the US Patent Office very kindly gave us a patent on. But it really uh it it we use it in mainly in our preamplifies. Um, but uh it's it it actually came in very helpful uh in this particular area, which is another reason why I have slight reservations with whether we can make something with tubes that'll do that'll do the same job. That of course doesn't mean that it doesn't work for other people, it just means it doesn't work for us.

SPEAKER_02 31:45

Ken, how does your speaker change the sound as you change the voltage?

SPEAKER_03 31:50

Um well it really does echo uh some of the things that that Rich was saying. You know, I mean as you so as you as you change the voltage, you're changing uh the driver parameters, and and as you do that, you know, in the system of the loudspeaker, the tonal character changes. So um so with a high voltage, and like in our power supply is up at the top end at 12.5 volts, um, you are lowering what's called the total Q of the driver and therefore the speaker. Um you're increasing the force factor, the VL, so the control that the magnet has over the moving mass. Um, and you're increasing its its damping factor, the self-damping of the driver. And um, and so you know what that what that translates to from the listening perspective is I I what I perceive subjectively, and what I think most people perceive is they get an even sharper image um out of music uh as you turn that um you know that uh voltage up. But um, but also the you know the the mid-range of the treble can become a bit more forward um in the overall frequency response uh with the higher voltage. Um but as you go down lower, uh you know that lowers or that raises the QTS, it lowers that self-damping factor. And um, and then for me, the subjective uh impression of that is that vocals and instruments have a rounder feel to them, it's a little bit warmer. Um, for me, the sound stage is bigger. Um, but you know, there's no free bunch. I mean, everything comes with trade-offs, and so you're losing a little bit of that razor sharp focus that you get um, you know, with the high voltage. Um, you know, but as you know, as Rich was saying, I mean, it really does just give you an opportunity to then you know tune that character, the character of the speaker response to all of the other things that are in that system. You know, you may have uh bright sounding components or cables that benefit from a little softening from uh you know a lower voltage uh presentation to the field coil, and and vice versa may be the case.

SPEAKER_02 34:11

Frank, have you ever had occasion to review or audition a field coil speaker and play with the voltage?

SPEAKER_01 34:17

No, never been able to play with the voltage. Uh my experiences have been at shows, and um I've heard many uh many speakers multiple times in multiple rooms, and um that's kind of what got me uh intrigued about all this, aside from the fact that I'm aware of the existence of you know field coil and being a guitar player, and you know, you're thinking about Al Nico and ceramic magnets and how all this stuff works. But um well, um, when are you guys exhibiting next? And can we ask the attendees to leave the room for 20 minutes and so that I can play with things? And for you, Frank, anything we can definitely play music that'll change. And my audiophile credibility will go down the drain. But uh actually, uh you know it's it it sounds like something that um would be a useful feature because it's like tube rolling, people have different preferences, and some people like the clarity of a telefunken, some people like the warmth of a a Mullard or you know, a bugle boy. And um so yeah, um I'll be at Capital Audio Fest, so you guys are there, you know. Um you might you might have to take me up on this. Yeah.

SPEAKER_05 35:39

Well, Frank, you're always welcome to Connecticut if you want to take the ferry up.

SPEAKER_01 35:42

Oh, yeah, right.

SPEAKER_05 35:43

The ferry movies want to just play around with fuel coils and have uh, you know, the first thing experience without the show stress. And um, you know, I just say that um, you know, like you mentioned with tube rolling, um, all this stuff is a recipe um to get the sound that somebody likes. So if you have to adjust the voltage, tuberl, at the end of the day, it's what makes you happy.

SPEAKER_01 36:03

Yeah, so what?

SPEAKER_05 36:04

So um, you know, I think some people get a little bit hung up in like it's kind of like some people don't want to hear like um you know, trouble and bass adjustments on a preamp. But if it works for you, that's ultimately what's most important.

SPEAKER_01 36:15

Yeah, well, I uh I really feel that uh and I've said this, you know, no system is really a hundred percent accurate. So if it makes you happy, I mean, if you like something that doesn't measure perfectly on an oscilloscope or something, you know, is that a bad thing if you're sitting there and you're loving what you're hearing at the end of the day?

SPEAKER_03 36:38

The pleasure of it is the whole purpose of the exercise, right?

SPEAKER_01 36:41

I mean, I think people lose sight of that, including when I when I was reviewing, even now, you know, I've got all my stuff here, and I spend way too much time sitting there squinting and playing the same records over and over and listening, and tell myself, you know, stop. What why did we get into this? Because we want to hear the music, you know, we want to have our minds blown by hearing the music on a level that ordinary systems can't reproduce.

SPEAKER_02 37:08

Question number six Is there any application in a loudspeaker where you think the field coil is not the right answer? Is there any situation in application in a loudspeaker where you think you actually think, even though you guys are field coil engineers, where you think the permanent magnet is the right answer for a particular application, maybe the tweeter? Uh Ken, what do you say?

SPEAKER_03 37:33

Um, you know, Ron, I this gives me a great opportunity to walk back something that I said in a prior video we did, which was at the Southwest Audio Fest. I was there with John Wolfe, and and that was a that was a great, great, uh, great video. I really enjoyed that. But but but in that video, I said that there was no loudspeaker, all of the things being equal in this building, it wouldn't be improved via fuel colour. Um, and in some sense, I still stand by that. But um, but I think there's a broader answer that is um perhaps a better one, which is that um you may find it surprising that I that a permanent magnet is almost always the better answer. And and I think that that's the case because there are so many other things in play for any loudspeaker manufacturer. You know, most of these manufacturers I think would have to you know dramatically change their business models and all the things that go into uh you know the complex considerations of what will in the end be a product out there in the world. And for many of these companies, I think, you know, mass manufacturability, repeatability, reliability, um, you know, some of the, I mean, just some of the things that come inherently with field coil Peter was mentioning, thermal considerations, that's a huge consideration for any loudspeaker designer that is putting something out there into the wild. Um, the extra complexity of you know the power supply and all the choices that a user can make around that. You know, I mean, if you're trying to put something out there as you know, a great sounding product that has you know broad appeal and can scale to a level that you know small manufacturers like Rich and I, for example, would don't even aspire to. Um, you know, I mean, it's just a no-brainer. Use a permanent magnet, that's the better route. Um, you know, if if if you're looking for the ultimate insonic performance and you don't mind taking on all of the things that you will be taking on by you know doing field coil loudspeakers, for example, you know, uh the fact that that really at that point, you know, when you're making a field coil and you've got all those variables in play and the variations in voltage, how that changes the parameters of the driver and all of that stuff, you're really making a system, you know, and so for me, that was perfectly fine because I was intending to, you know, to make in essence a work of art that was going to be in part comprised of the field coil, but then you know, I had the freedom to take all of those other you know things into consideration, uh, you know, under the the presupposition that I'd be a very small producer. So if you're a small producer, if you know uh the cost and complexity that you incur uh from a field coil versus a you know a good permanent magnet structure doesn't scare you off, um then you know, then I would say that in that case, uh all things being equal, a field coil loudspeaker is is always going to somewhat improve you know the the overall calculus of of any of any loudspeaker um that you might consider. But there's just so much more about it that if I were advising people, I would say that permanent magnets are more often the more sensible choice.

SPEAKER_05 40:53

Rich. Yeah, I mean, I definitely agree with everything Ken said. I think um, you know, with mainstream manufacturing, um, even in the very high end of things, um, it depends on what the engineering goals are. I mean, if you look at like the uh the new Wilson autobiography, um, with a bunch with a lot of drivers, and some of them are small sealed enclosures, there's no way to ever thermal manage that situation without dramatically changing the design. Um, and you know, they're very concerned about it on you know time coherency and things like that. And that just wouldn't lend itself to a field coil. I mean, in an ideal world, if you could just make those drivers a field coil, there would probably be a benefit, but it has its own engineering drawbacks. And then speakers with a lot of drivers, each one then has its own power supply. This becomes you know exponentially more complex. So, you know, I agree with Ken completely. In an ideal world, if you could sprinkle field coil dust on the driver and make it a field coil, you're gonna see an improvement. But the reality is with engineering, is that's not always the case.

SPEAKER_02 41:55

Peter, audio note makes both field coil and permanent magnet loudspeakers.

SPEAKER_00 41:58

No, we don't. Um, I have a somewhat different view to on this. I mean, I think a laptop with a loudspeaker in it, like the one I'm sitting here with, uh, that would not benefit from the field coil. Um I don't think that there is a single argument for using if you take a$500,000 pair of speakers and you're not using field coils, you're lying to yourself that you make the best. I have a much, much harsher view of the way the industry operates, and I have had that for the last 50 years, which is how I've ended up going in the direction I've gone in. I think that that it's there's a kind of dishonesty associated with engineering, which claims to be the best and to have the best and just be the best. And then you look at the materials, you look at the way things are made. I mean, I I had the I was at in the Singapore show last year, and I walked in as a Danish manufacturer. I'm Danish by birth, so uh I have a I can speak to them in my own language and insult them properly. Um that was great fun. Uh and they they make these claims for these uh speakers, they make which uh cost, I think it was 1.1 million uh Singapore dollars. And I said to him, so you know, what have you what what magnet systems are you using in? He said, Well, you know, we're we're using these special magnets. Look, I've been doing this for 50 years. I know more about the metallurgy in this shit than than you've had hot dinners. And I I I I don't take this bullshit. I'm very sorry. You know, and and yeah, I come from a country where a spade is a spade and a shovel is a shovel. And if you don't like that, which of course is you know, a lot of when I moved to Britain, a lot of people felt that I was very rude. I am probably as well, but uh a lot of it is in the language. There are no excuses for for speakers that are a hundred thousand dollars off for not having field coils. It's that simple. And it is simply a question of where you allocate the cost. Now, if you have 30% of your cost base used for advertising, then you can't afford to put field coils in your speaker. It's that simple. And it you know, I'm I'm sorry to say that that and I I've I know most of the speaker designers, um, at least of of your not the modern, more modern ones. I can't go around so much anymore. But I I I don't think, you know, if you look at if you have a very small speaker, you know, a little Rogers Ellis uh 3.5A, you couldn't put a few peripheral calls in those. That simply wouldn't be possible. And the same would apply to to a lot of things that are at the very, very low end of the cost scale. But if you are claiming, as the high-end industry does, to have speakers and make products that are the ultimate, then making something that doesn't have a field coil in it is a lie.

SPEAKER_02 45:43

It is that simple. Well, so talking about the subject, let's jump to question eight, which is directly relevant. Can can you guys imagine traditional loudspeaker manufacturers, big blue chip companies like Magico or Wilson ever moving to field coil drivers, even if not for every driver, because it would be a very complicated thing to put that in a in an XVX, but maybe even just for the the base drivers and the mid-base drivers.

SPEAKER_00 46:13

Look, it's it it's uh I'll I'll repeat what I say that's very simple here. You can't mix field coil drivers with non-field coil drivers. You can't mix them. The behavior of the drivers are so different in terms of stop and start parameters that you you simply cannot mix them with uh a base, a 15-inch base, for example, with a huge uh ferrite magnet.

SPEAKER_02 46:42

Even if you go above, couldn't you make the upper mid-range and above non-field coil and the mid-base and woofer below field coil?

SPEAKER_00 46:53

I think the disparity in the way they resolve the material they're presented with would make that very difficult to listen to.

SPEAKER_02 47:01

Interesting, because for example, the Wolf on Langa speakers, the Sone is a field coil woofer mid-range, and then it has a little ribbon tweeter thing on top. Um, so I mean, different designers have different philosophies, obviously.

SPEAKER_00 47:12

I would that that's that's true. Some of it is done in order to uh create a kind of of uh fake novelty.

SPEAKER_01 47:23

Well, maybe they feel like having one driver is better than none at all. You know, that that was actually one of my questions, where um, you know, some designs I see uh field coil with tweeters, others with woofers, otherwise others trying to go full range. Um, you know, would it would it be a worthwhile compromise to have one field coil driver and the rest uh you know conventional drivers, or it's an exercise in like you're chasing your tail?

SPEAKER_00 47:57

I think you're chasing your tail. I don't think I I think again the industry, the industry has a tendency. I mean, I'm talking broadly speaking now, I'm not talking about absolutely everybody in every corner of the world, but the industry has a tendency. I mean, you you look at the uh the Andrew Jones speaker that's just come out, that uses a a concentric mid-range tweeter with a field coil and a normal um uh woofer, presumably with with um a ferrite magnet. Yeah, I don't know. I haven't personally heard them, but one of uh my one of my sales guys who's a professional musician, um, or was a professional musician before I hijacked him, um he basically uh he went down and listened to it, and he said the bass was all over the place. You could clearly hear that the bass was incapable of tracing what the uh what the opera rangers were doing. And that's exactly what you get if you try and mix it. And and you know, I'm not into apologism, I'm not into this. I find it I find it irritating. It it is it's simply not the case that you can mix these successfully and make something that's of truly high quality. That is done for market, that's done for marketing and nothing else.

SPEAKER_02 49:32

Ken, what do you think? Why wouldn't a traditional manufacturer like a big company like Magico or Wilson or uh like that consider field coils? Is it partly a not invented here problem, or what are your thoughts?

SPEAKER_03 49:44

Oh no, I don't think so. I mean, field coil technology is what over 150 years old.

SPEAKER_00 49:49

I mean uh No, it's not. It's nine well it it it goes back to Earth State. The the electromagnet uh goes back to Earthstead in the 1850s. But the first, I mean, when Kellogg and Rice introduced uh the put the patent in with the US patent office for the first moving call loudspeak on Got the patent that used the field call.

SPEAKER_03 50:13

Sure. Yeah, but but in other words, it's not it's not something that you know was uh you know, field coils are obviously not a recent phenomenon. So I don't I don't think that's a part of it. Yeah, it's um you know, I mean, I it returns back to I just can't imagine that you know many companies of that scale. I mean, I guess focal would be an exception. I think in their highest range of speakers, they use field coils for like the Grand Utopia.

SPEAKER_00 50:39

One one one driver.

SPEAKER_03 50:41

Yeah.

SPEAKER_00 50:42

That's smart enough to know that the base unit benefits the most.

SPEAKER_03 50:47

Yeah, I I I mean, as far as you know, as far as looking at my own designs, um, I would I would definitely agree with Peter that the S2 is a compromise. Um, you know, I mean, if I would have had uh, you know, enough uh resources and time, and you know, I mean there's only one Ken, so you know, I'm kind of doing all the work. And but if there was infinite Ken and infinite resources to go around, I mean, would the S2 be using uh a permanent magnet woofer? No, it wouldn't. Um, so I'm I'm I'm helpless to agree with Peter that he's I I agree that he's right about that. Um you know, one of these days, you know, I'd like to revisit that loudspeaker as a you know an entirely field coil speaker, or um, you know, maybe move on to the next project and whatever the next you know overall loudspeaker design will be for us. But um, but returning to your original question, now I mean I don't think that Magico or Wilson, you know, companies like that, Rockport, you know, I mean, any of those big blue chip players will move to field coil because just from a business perspective, I don't think it would make sense for them. You know, I mean, just when you think of the realities of how many points they give up and dealers and distribution and their marketing budgets and the fleets of you know people that are out there trying to sell their work, you know, I mean, just in terms of their margins alone, I just can't imagine that field coils would ever be a sensible decision. But you know, but I'm with you, Peter. I mean, every single one of their loudspeakers, if engineering permitted it, would sound leagues better as field coil loudspeakers. No question about it. The the only um, you know, and and then returning to what you said previously, then you know, the issue as I see it is the claim they make. It's it's not that they've chosen to make permanent magnet loudspeakers, it's that they claim it's the best. That's really the correct but isn't that isn't that the problem?

SPEAKER_00 52:58

I mean it's misrepresentation. Yeah, yeah. Well, I mean it's a it's no, I mean there's a word for this in the English language. Why don't we just use it? It's misrepresentation, it's not the best. Yeah, I'm I'm agreeing with it. They don't even use an ecomagnets, yeah.

SPEAKER_03 53:15

I I'm agreeing better than pharietes. Yeah, I I don't disagree. I I agree with that.

SPEAKER_00 53:21

It's just bullshit. I mean, let's call the spade a spade here. It just doesn't make it doesn't make sense to me. It you know, and I I I can't, yeah, I can't I you know the idea that you can somehow use an inferior driver magnet system and then somehow compensate for that by making some clever shit in the crossover, or change the shape of the cabinet, and that then compensates for this. This is just it's just cosmetic. It has very little effect. And the the reason that they think this makes a difference is that when they measure the speaker, they get a certain set of parameters depending on how they measure them and where they measure them. But that's the the the fact that that somehow helps their case just goes to prove that the measurements are inadequate, you know.

SPEAKER_05 54:22

Well, if these things were cards, we need a different use listening either. Because I I have to I have to agree with a lot of it. Um, you know, I think these blue chip manufacturers, maybe they're so down, so far down their paths that changing at this point might be such a tear up to their product. But um, you know, you see a lot of you know the seven-figure speaker now on the market, you know, like we saw the exponent a couple rooms. Um maybe field coil will be the thing that pushes it to the$1.5 million ultimate flagship. Who knows? But um, yeah, I think um, you know, you can't take low-quality ingredients and make them superb. You're better off starting with a better foundation. And um, you know, field coil is the better foundation. Um, just a matter of, you know, if somebody wants to put the resources in to implement it properly.

SPEAKER_01 55:14

Well Frank, please weigh in here. Yeah, I could turn that around a little bit. Um, what are the possibilities of advancements in field coil technology, like say new materials or um things that you didn't have access to five or ten or a hundred and fifty years ago? You know, what's the potential to make field coil speakers even better? Or have they evolved to, you know, you think they got it right up, you know, in the I don't think they I don't think they have.

SPEAKER_00 55:49

I I think the the the problem with this kind of research is we spent over a period of about six years, we spent half a million pounds, which is what uh seven hundred thousand dollars on.

SPEAKER_01 56:07

I said it's out of my pay range.

SPEAKER_00 56:09

I my mind doesn't it's out of my bloody pay range as well. I can tell you I can't pay myself that well. That's that that's beside the point. Oh, well, they they they this this kind of of research into metallurgy and the behavior of materials is something we uh uh audio note as a company has spent a huge amount of money on. Over you know, we we have a budget for RD for of about half a million a year.

SPEAKER_01 56:38

Some of the back in tax kind of look at what goes into your amplifiers, you know, and there it is.

SPEAKER_00 56:45

It goes into developing resistors, it goes into developing capacitors, it goes into developing uh better heat treatment methods for all the soft iron that we use in our upper transformers. Um, and it were, you know, some of that research could then be well was we had the advantage of some of that research was then usable and when we started looking at the field corals more seriously. And and I have no doubt that that we can improve it uh further, but I don't think modern materials are going to do it. The the the iron we use is i is iron that was designed in the 1900s. It's not iron that it is it's not modern iron. The top plates are modern iron, that's Tel R57, which is it's known in Europe as Swedish steel. But the the uh the uh the the base cup um of the uh is is uh is uh as a kind of carbon steel that was used in the uh in the 18 uh in the 1800s. So, you know, this is not new. What I find so interesting as a as a just as a side comment is the fact that here we're sitting discussing a hundred-year-old technology, and it is clearly superior to everything that's come after. A second issue is, of course, that when the when this was removed in the 1930s, uh when the hard uh magnetic materials came in, the all the drivers that were used for field coils were generally full range. They were not used for woofers and tweeters, that only came in in the early 30s when uh when Western Electric and RCA uh started making cinema sound.

SPEAKER_02 58:50

Question number eight. Okay. If I had on the show right here with you guys a measurements objectivist, is there one particular objective measurement which demonstrates the technical superiority of field coil drivers? If we had a two traces telescope and one trace was the output of a field coil and one trace was the output of a permanent magnet speaker, what is the one objective measurement that you can persuade people is objectively superior with field coils?

SPEAKER_00 59:21

I don't think you need our oscilloscope for it. I think you need something that uh that measures magnetism. You know, you you have to look at the house to reach this loop.

SPEAKER_02 59:33

That's too complicated. I want to say something where it's a smoother wiggle, smoother wiggle, and that's why it sounds natural and smooth. Something like that. Oh, you can't measure that. Okay. Anyone else?

SPEAKER_00 59:51

How do you think we ended up with shitty permanent magnets?

SPEAKER_02 59:56

I want to make an objectivist happy with this. No, nothing we can do.

SPEAKER_05 59:59

I'll throw you, I'll throw you a basic answer. Um, you can measure efficiency, frequency response, and um impulse response are a little bit different with the field coil.

SPEAKER_02 1:00:09

Why would frequency response be different?

SPEAKER_05 1:00:11

I think you can because of the uh magnetic field, the flux.

unknown 1:00:15

Oh, okay.

SPEAKER_00 1:00:16

But you're right, actually, Rich. There is a s a small difference in the uh in the uh impulse response. But the problem, but the problem is that that can be created through changing materials, for example, in a in a speaker with a permanent magnet. So it's not a it's not a guaranteed.

SPEAKER_04 1:00:36

Yeah.

SPEAKER_00 1:00:38

The hysteresis loop is the one you can't run away from.

SPEAKER_03 1:00:42

So Peter, what about what about that uh stiffness of the magnetic field you were mentioning? And I'm asking this to improve my own understanding. Like, you know, as I have often um, you know, just tried to come up with a a conversational way to talk about permanent magnets versus field coils. You know, it shows with people who are coming in and out of the room. Um, you know, I've often described uh the you know the the magnetic field stiffness of a permanent magnet to be much like a trampoline. And as it attempts to stop the moving mass at a point in space, return it to a resting point, um, it's always overshooting the mark one direction or the other. And that the field coil um has absolutely immense control over that motion and can stop it at exactly the point in space that it should arrive at and return it to a resting state with equal accuracy. And um, and and so for me, you know, I've I've I mean I don't know if that would be uh you know considered like transient ringing or you know, whether that is just simply a matter of the self-damping nature of the field coil versus you know the outer limits of self-damping capability of a permanent magnet driver. Um, you know, what do you what are your thoughts on that?

SPEAKER_00 1:02:06

Well, I mean, they the you know, if you look at how how base modern base units are designed, they have very long speech coils. The field itself is in most cases maybe eight to ten millimeter. That's where the the real field is. Right so you put a driver, you put a speech coil in that's uh that's uh say 25 millimeter. Now the theory is that the amplifier has more control over that because it it it when it moves, there's always some part of the coil that's in the field. Sure. And therefore the amplifier stamping factor sh uh has some control of that. And you're describing in a in an overhung design. Yeah, and the overhung design. The problem with it is that all the energy that is put through the coil, the speech coil, that is not in the field is dissipated as heat. So it's extremely inefficient, right? And which is how we end up with 200 watts and 300 watts. I mean, you guys, like we do, we make small amplifiers. Right, you know, the smallest amplifier we make is 1.7 watts.

SPEAKER_03 1:03:22

Yeah, and our field coils are in underhanging design.

SPEAKER_00 1:03:25

I mean, I remember showing the first single-ended triode amplifier at the Chicago CES, it goes back that far in 1987, and it was seven and a half watts. And I had people coming in, looking at it and laughing and walking out again. They didn't even listen to it. I still have that happen to show.

SPEAKER_03 1:03:53

They see my single field, my single driver loudspeaker, and they literally like they make a sour face and they turn around and they walk it.

SPEAKER_00 1:04:01

Yeah, but that but that's I mean, uh a probably designed single driver loudspeaker is perfectly capable of covering the the range from 40 to 50 to 15 kHz. Sure, cheers to that. And and yeah, I mean, they were designed by Paul Voigt in the early 1930s. Yep. And they used field cards as it happens.

SPEAKER_02 1:04:27

Okay, Frank, any final thoughts?

SPEAKER_01 1:04:30

Um, yeah, well, um, I wrote down in big capital letters here. The implementation of a technology can be more important than the technology itself, but you guys addressed that like three minutes into the show. Um you um I'm just wondering, um, you know, I I'm a fan of Planar Magnetic and Ribbon and AMT uh tweeters. You know, I wonder what the uh planar guys would have to say as far as why they would choose those kinds of drivers over uh field coil. You know, I know uh we should probably have a representative uh, you know, emotion emotion transformers.

SPEAKER_00 1:05:11

Uh we should have an idea for the next episode.

SPEAKER_01 1:05:18

I always have, you know. Uh, but but my thought is always, as you guys, you know, said, um, it's not just a question of, well, here's this technology, it's better than everything else. It's how you implement it. And yeah, I do have one more question. When did you guys first hear of a field coil speaker? And what turned you onto it and made you decide you wanted to, you know, pursue this.

unknown 1:05:45

Rich?

SPEAKER_05 1:05:46

I'll go fast. Um yeah. So um you know, I didn't plan on getting into speaker design. Um, I'm an industrial designer by trade, and um a friend of mine bought a pair of these. Rule of drivers, and he's the type that kind of buys a bunch of stuff and sells it all and then buys it all and sells it all. Um, like an O C D kind of um, and I bought him on a whim, and um I was just like you know, Ken's experience with his first driver, I was just blown away with what this thing was doing, you know, air and raw on my desk. And I was like, I need to turn this into a thing that other people can enjoy because it's so fantastic and so like things I've heard before.

SPEAKER_01 1:06:30

There's a real quality to it that that you can hear. I mean, to me, I can hear it instantly, and you know, my hearing certainly isn't what it was, but there's there's a flavor to it, if you will, that I think is immediately apparent, which is what has gotten me curious about the technology and makes me want to you know seek it out at shows and and hear more.

SPEAKER_02 1:06:54

Ken, how would you answer Frank's question about what first turn do you want to feel about?

SPEAKER_03 1:06:59

You know, um, I don't know. I mean, I I guess for me, I don't know, there's there's some book. Uh I can't remember whether it's just called like the toaster project or something like that. And it's it's a really interesting book where the author is exploring everything that goes into just making a simple toaster, you know, that you may find, you know, on the shelf of of any grocery store and all the the you know the the materials, the mining, the people involved, I mean, just everything. And he and he sets out on the endeavor to make a toaster. And as you can imagine, chaos and polarity is through as he as he tries to do that. Um and and for me, putting together the field coil, its birth for me was a very similar sort of project. Um, you know, I I had for personal reasons reached a point of you know really doubting my life choices of getting into software and how I was spending my time, you know, and all of that. And um, and I'd long had you know a love of music and had been designing loudspeaker cabinets for quite a long time and filling up our house with that kind of thing. And um, and I'd just been obsessed in the back of my mind with the idea of building the entire loudspeaker from scratch, the whole thing, no compromises, as just one continuous you know, piece of art. Um, so that was really how the obsession sort of arose, you know, for me, doing the entire thing myself, the comb work, the surrounds, the metal work, you know, the magnetic circuit design, the whole thing. Um, and um and really just as an artistic accomplishment. Um so you know, that was where it got started for me. And and believe it or not, the first field coil that I ever heard was that one that I made. Um, you know, I I waited, I waited, believe it or not, until my wife was out of town on a business trip because I was so nervous about turning them on, I almost couldn't bear it. I mean, my heart was just pounding out of my chest. Um, you know, as I was taking these things into our guest bedroom and connecting them to the amplifier and just hoping to God that they would make sound at all, you know. Um, and so I just set them in free air on the carpet, and I had a subwoofer that I had, you know, made myself, you know, sitting in the corner of the room. And you know, I mean, when I hit play, I had no idea what was going to happen. And what came out of those drivers was just beyond belief for me. I mean, just absolutely beyond belief. You know, I'd I'd owned a lot of speakers, you know, over a long period of time. And I I think it was it was more than just one thing. I mean, I think for the most part, it was it was you know, it was the field coil in combination with hearing uh a well-designed you know, full-range point source for the first time and the phase coherency that went along with that. Um but that was but that was really it, you know. Okay. Okay.

SPEAKER_02 1:10:06

Yeah. I'm gonna make two quick comments on uh Frank's questions. I agree, Frank, completely. Implementation Trump's theory. I say it all the time. Uh very important concept, I think, implementation Trump's theory. And that's why I very much appreciate that you are mercifully not dogmatic and you just go by what you hear. I like that from uh when we hung around uh walked around at Exponent. Secondly, I've been a planer person my entire life. I have literally never in my life owned a box speaker, and I love the field coil sound. I've loved every single uh speaker I've heard. There's a magic to the mid-range, but there's just still something to the open presentation of the planers that just idiosyncratically works for me. On to the music segment. Who has a music recommendation for us? We have to go kind of quick.

SPEAKER_00 1:10:52

Well, I have one, please. It's 15 boxes, time life, the swing era, three box uh three records per box, comes with a little booklet that's very informative. You can pick these up on eBay for virtually nothing. There's 15 boxes of them, so 45 records. I reckon you can pick them up for a couple of hundred dollars from the first.

SPEAKER_02 1:11:19

What's the name of it exactly? How does somebody search for it?

SPEAKER_00 1:11:21

Oh, the swing era. Okay. And uh people look at them because they're dated from the 30s up to the early 50s, and most people think they're 78 transfers. They're not, they're remakes from the late 50s until sometime around 1967. They are rearrangements using the original musicians recorded by Capital. They are amongst the finest recordings ever done by big uh of big band music, and you can pick them up from nothing. They they beat any of the uh of the audiophile releases of that ilk by a country mile. They're cheap, they're available. So that was my from my first. I can rattle off a whole load of them if you like, but uh, this is this is my favorite. Um I I I think it's very sad to see them being thrown in the trash because people don't buy them. Rich, what have you got for us?

SPEAKER_05 1:12:25

So, you know, I like a lot of indie stuff, and I'm never really one to seek out good recordings, I'll be honest. Um, I like the new the new new pornography's album is actually really good. It's good fun. Um what's the name of the album?

SPEAKER_02 1:12:37

What's the title?

SPEAKER_05 1:12:38

Um The Former Sight of. Um, it's great. Um, and I just I listen to a wide variety of stuff. I love electronic music and I listen to music that you wouldn't think you'd play in a 300p amplifier, is probably the short answer. If it's Night Nails or it's Japanese breakfast or Swerve Driver, yeah, I'm all over the map, but um I I also kind of I'll briefly throw out the fact that sometimes I like hearing earlier recordings where they're not done well because it it captures the essence of the band in the moment. Um, you know, I love the Smiths, they didn't have any money during their first recordings, so I appreciate the fact that it's not 100%. And you kind of hear that vibe of the studio at the time, and you know, I kind of appreciate that for what it's worth. And a great system shows that it shows that you know it was recorded in a cheap studio and didn't have a lot. And I I like that too.

SPEAKER_02 1:13:32

Well, funny you mentioned the Smiths. Uh, Max Pavel and his father, Max is the uh Hi-Fi Five's youngest fan. He's the kid I met at Expona. He and his father on Saturday brought over the Smiths. I don't even know the band, it was a horrible recording.

SPEAKER_03 1:13:47

Yes, maybe not for us. All right, I'm gonna be a disappointment, Ron. I don't know.

SPEAKER_02 1:13:53

Um, okay, we're moving to Frank. Frank, I know you've got stuff for me.

SPEAKER_01 1:13:57

Well, the British singer rumor, R-U-M-E-R, been around for about 10 or 15 years. She's got a voice that you know you'll just melt. And uh her her recordings are good, especially the one where she covers Bert Backrack songs called uh This This Girls in Love. Uh, every time I played at an audio show, all the out the cacas just melt into their chairs, you know, myself included. And one for Rich, uh, I was kind of shocked. Um, Rhino just reissued on Vine Stooges Fun House. And it's I thought it was just gonna be like a wall of terrible noise. I mean, in terms of the recording college, but it's like an audiophile recording. The bass sounds like it's right there. Iggy is in your face.

SPEAKER_05 1:14:47

I have to check that out.

SPEAKER_01 1:14:48

It'll blow some minds at Capital Audio Fest or wherever you're gonna be next. Nice, but yeah, if if your taste, you're gonna flip, you're not gonna believe it.

SPEAKER_05 1:14:59

Nice. I'll definitely check that out.

SPEAKER_01 1:15:00

If you like English, English singers, Frank. Yeah, I can barely make it out. Weathering the storm. Oh god, this okay. Well, I'll see that when you replay the video, but uh yeah, and all right, I'll change that.

SPEAKER_00 1:15:22

Joe Harrow.

SPEAKER_01 1:15:24

Yeah, make it a note.

SPEAKER_00 1:15:25

This is really this is really worth listening to. She's got a great voice. There's a lot of good female singers around now. Yeah, I know. It's Amara Joy. It's really it's really uh surprising how many great voices there are.

SPEAKER_01 1:15:42

Yeah, yeah.

SPEAKER_02 1:15:44

Okay, gentlemen, this has been great.

SPEAKER_01 1:15:46

Anyway, guys, lots of fun. Thank you.

SPEAKER_02 1:15:49

Uh all right, as you know now, viewers, the Hi-Fi 5 is live the second Wednesday and the fourth Wednesday of every month. The next episode is May 27, back to our regular time of 6 p.m. Pacific, 9 p.m. Eastern. Gentlemen, thank you very much, everybody. This has been great. Thanks so much, Ron.

SPEAKER_01 1:16:06

We enjoyed it. Yeah, thanks. Good to good to see everybody. Yeah, nice meeting everyone.

SPEAKER_05 1:16:12

Good meeting you.

SPEAKER_01 1:16:13

Okay, all right.